Shaft of telescoped sections



April 23, 1968 P. DURAND SHAFT OF TELESCOPED SECTIONS 2 Sheets-Sheet 1 Filed Oct. 24, 1965 FiG.5

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INVENTOR P/Ekk Du/M/vo BY ATTORNEYS April 23, 1968 P. DURAND 3,378,978

SHAFT OP TELESCOPED SECTIONS Filed Oct. 24. 1965 2 Sheets-Sheet 2 87 ics] F Fi G10 15 \U \J: .JJL-

INVENTOR /aees pupa/v0 BY PJM ATTORNEYS United States Patent 3,378,978 SHAFT OF TELESCOPED SECTIONS Pierre Durand, Lyons, France, assignor to Richier (Societe Anonyme), Paris, France Filed Oct. 24, 1965, Ser. No. 504,440 Claims priority, application France, May 21, 1965, 46,028, Patent 1,444,294 2 Claims. (Cl. 52632) ABSTRACT OF THE DISCLOSURE A telescoping tower has polygonal upper and lower sections that telescope within each other. The apices of the upper section are located adjacent midpoin-ts of the sides of the lower section. The lower end of the upper section has a plurality of triangular prisms one secured to each of its sides, these prisms adapting the lower end of the upper section to slide in and to be selectively secured to the lower section of the tower.

My invention has for its object towers of a polygonal cross-section, the parts forming such towers having different areas and more particularly, my invention relates to crane towers constituted by a main lower part and an upper jib-carrying part fitted telescopically inside the lower part.

In cranes of said type, the sides of the upper part carrying the jib are parallel with the sides of the lower part and the difference in cross-sectional area between the two parts cannot be large, unless an intricate structure is provided for transmitting from one part to the other the torsional and flexional stresses applied to the framework of the crane-s.

The upper section of the tower is of substantially less cross section than the lower section and is adapted to slide in and be selectively secured to the lower section by means of a plurality of prisms one secured to each side of the lower end of the upper section, so that the apices of the upper section are disposed adjacent the midpoints of the sides of the lower section.

FIGS. 1 to 4 of the accompanying drawings show furthermore in elevational and horizontal cross-sectional view respectively two conventional embodiments of the connection between the upper and lower parts of a crane tower.

In the case illustrated in FIGS. 1 and 2, the difference in areas between the lower part 2 and the upper part 3 is comparatively reduced; the connection is then ensured by a frame 4 which rigidly secures .the members or ribs forming the two parts and ensures the transmission of the stresses between said parts.

In the case illustrated in FIGS. 3 and 4, the diiference in areas is in contradistinction large and would lead to a prohibitive size for the shaped members forming the frame. It is then necessary to ensure a connect-ion between the parts 5 and 6 of the tower by means of a triangular system 7 the execution of which is an intricate matter since the space available between the two parts of the tower is restricted.

The problem to be solved can thus be summarized as follows:

Either the d-ifierence in transverse size between the two parts of the tower is small and their connection is easily obtained, while, however, the upper part of the tower shows substantially the same characteristics as the lower part, which leads unnecessarily to an excess weight and to an increased cost;

Or else, the difference in transverse size is large and the connection between the two sections of the tower can be obtained only with difiiculty.

Patented Apr. 23, 1968 The' present invention solves the problem by providing between the parts of the tower a difference in transverse size such that they may be inscribed inside each other in a relative position in which the edges of the upper part engage the lateral surfaces of the lower part.

Said arrangement of the two parts of the tower leads to different applications among which should be mentioned by way of example:

The execution of a change in cross-section of a tower or mast,

The execution of the upper part of a crane adapted to be raised through a telescopic connection,

The execution of the upper part of a crane adapted to be telescopically collapsed within lower parts of different cross-sectional areas.

-My invention, its advantages and other features will appear clearly from a reading of the following description, reference being made to the accompanying diagrammatic drawing illustrating, by way of examples, diiferent embodiments corresponding to the three above-mentioned applications.

'In said drawings:

FIGS. 1 to 4 illustrate prior art as disclosed hereinabove.

FIGS. 5 and 6 are views respectively in elevation and in horizontal cross-section of a tower improved in accordance with my invention.

FIGS. 7 and 8 show in perspective view two embodiments of the connection between the two parts of the tower.

FIG. 9 is an elevational view of a crane tower of which the upper part designed in accordance with my invention is telescopically collapsible.

FIG. 10 is, on a larger scale, a detail view of the lower end of said tower.

FIG. 11 is a horizontal cross-sectional view of an embodiment of the lower end of the upper part of the tower.

FIG. 12 is a horizontal sectional view of a tower having a triangular cross-section, which tower is designed in accordance with the invention.

The change in cross-section between the upper and lower parts 8 and 9 of the tower illustrated in FIGS. 5 and 6 may be obtained in the manner shown in FIG. 7.

Above the plane P shown in FIG. 7, the upper part of the tower includes, as illustrated in said FIG. 7, four shaped members 8a, 8b, 8c, 8d which are interconnected by stays andcross-braces not illustrated and which extend underneath said plane P of FIG. 7. The lower part of the tower is constituted by four shaped members 9a, 9b, 9c, 9d and the two parts of the towers 8 and 9 are angularly shifted with reference to each other in a manner such that the upper shaped members 8a, 8b, 8c, 8d each engage lines extending at mid-height along the corresponding side of the lower part of the tower the upper part 8 having of course a cross-section which is much smaller than that of the lower part 9.

The connection between the two parts 8 and 9 of the tower thus positioned is obtained by means of a triangular system constituted by two straps 10 and 11 and four pairs of stays arranged in the shape of inverted Vs as shown at 12.

It should also be remarked that, as illustrated in FIG. 8, said connection may be simplified by omitting the strap 11.

Said arrangement of a tower allows, as mentioned hereinabove, executing an upper part of a crane tower adapted to be raised by means of a telescopic connection as in the case of the crane illustrated in FIGS. 9 and 10.

Taking into account the height of such a type of crane, it is necessary to give the lower part 13 of the tower a cross section which is much larger than for the upper part 14 of which the cross-section is defined chiefly by the diameter of the gear wheel 15 controlling the pivotal movement. Since, however, on the other hand, it is necessary for said upper part 14 to slide inside the lower part 13 of v the tower and the stresses exerted in the shaped members should be properly transmitted from the upper shaped members to the lower shaped members, it is necessary, according to my invention, to constitute said upper part 14 by superposing two sections of different cross-sectional area, as illustrated at 16 and 17.

The section having the larger cross-section 16 is located under the upper section and serves both as a sliding member and as a connecting member with the lower part 13 of the tower.

The section having the smaller diameter 17 carries the gear wheel 15 controlling the pivotal movement and the diameter of which is independent of the total height of the crane and depends only on the torque produced by the load at a maximum reach.

FIG. 10 illustrates furthermore diagrammatically said portion of the tower. The shaped members corresponding to the smaller section 17 of the upper part 14 are fitted to the lower section through the agency of a frame 18 the sides of which are parallel with the geometrical diagonal lines of said section 16, whereby the stresses at the points connecting said frame with said stays are transmitted through the stays to the shaped members or ribs forming the section 16 and thence to the shaped members or ribs forming the lower part 13 as provided by assembling the cooperating shaped members together.

My invention allows, inter alia, executing an upper part of a tower adapted to serve in cooperation optionally with either of two lower parts of different cross-sectional areas.

The upper part of a tower may, in fact, include a lower extension fixed to the lower part of a tower, which lower .4 part is slightly larger, so as to allow the sliding of the upper part. It is, in fact, possible to associate with such an extension four triangular prisms 20, or else dihedrals (FIG. 11) said extension being adapted to slide in and to be secured to the lower part of a tower.

Obviously, my invention is not limited to the embodiments and applications described by way of example and it covers in fact all the modifications thereof falling within the scope of the accompanying claims. In particular, the cross-sectional shape of the tower may be modified and be for instance triangular as illustrated in FIG. 12.

What I claim is:

1. A tower comprising a lower section of polygonal cross section and relatively large cross-sectional area and an upper section of polygonal cross section and relatively small cross-sectional area, the apices of the upper section being located adjacent the midpoints of the sides of the lower section, and a plurality of triangular prisms secured one to each side of the lower end of said upper section to adapt said upper section for vertical sliding movement in and selective securement to said lower section.

2. A tower as claimed in claim 1, said triangular prisms each having a fiat side secured to a side of said upper section, the other two sides of each prism being coplanar with the sides of the adjacent two triangular prisms.

References Cited UNITED STATES PATENTS HENRY C. SUTHERLAND, Primary Examiner. 

